This proposal for a diagnostic and investigative laboratory (DIL) will provide MIT faculty a resource to support their utilization of laboratory animals in biomedical research. Over 125 principal investigators maintain an average daily census of 16,000 animals. Animals, receiving daily veterinary and diagnostic support, are maintained under the Division of Comparative Medicine's centralized management in approximately 80,000 GSF of AAALAC approved animal facilities. The laboratory also provides diagnostic services for 21 Boston area biomedical and academic institutions. This laboratory, as part of the Division of Comparative Medicine, has a long term goal of fostering humane care and use of laboratory animals, providing diagnosis and treatment of laboratory animal diseases and providing new knowledge for the field of comparative medicine. The specific aims are: 1) to operate a DIL for the diagnosis and prevention of disease of laboratory animals utilized by MIT and the Boston biomedical research community and expand research efforts in relevant areas of the biomedical sciences, and continue the development of new and/or improved diagnostic tests; 2) to investigate new relevant disease that are identified by the diagnostic resource; 3) to continue the characterization of ferrets as animal models and to pursue the study of rodent animal models for Lyme disease; 4) to continue research on gastric and enteric diseases of laboratory animals; and 5) to expand and improve our program in teaching and research training in laboratory animal/comparative medicine and comparative pathology for graduate, undergraduate and summer veterinary students. It is essential to the overall research program at MIT that the DIL and comprehensive veterinary support be available.